Bond thing (not James though)

So I'm still reading Wheel of Time series and there was this bonding thing (no I don't mean BDSM kind of bonding). Basically there were those female magicians who had those knight-like bodyguards and they had this spell casted on them that let them know where they are, what is their condition etc. Usually those mages had a single knight of their own. There were certain side effects to the spell though. The mages became emotionally attached to the knight (and vice versa) and some even married each other and those who didn't still thought fondly of the other one (like of a close family member).

Sure there are plenty of contracts things in manga and anime, but I'm looking for something where the "bond" actually affects both parties (like emotionally), something where the bond makes both of them change (and slightly against their will at that).

I had two examples from the manga world in mind but now I only remember a single one. Sekirei actually had that kind of bond thing. Most sekirei were falling in love with the person they had a contract with (even if they didn't want to), though most of the "masters" were not really affected by the bond (Minato and a few others were an exception).

Please no: Hentai, Shounen Ai, Shoujo Ai, Reverse Harem (one girl multiple guys)I'd prefer series with some romance and where the "bonded" characters are a girl and a guy.